Abstract

Future communications systems are expected to enable interaction between an increasingly diverse range of devices, both mobile and fixed. This will allow users to construct their own personal distributed environments using a combination of different communications technologies. Depending on the services' availability, the communication configuration could be, for instance, via a cellular system, a wireless ad hoc network, a digital broadcast system, or a fixed telephone network. This new form of communication configuration inherently imposes strict requirements on security, especially when the number of involved entities, accessible network nodes, and service providers increases. The creation of such heterogeneous, dynamic, and distributed networks raises many technical issues. The paper discusses the particular problems involved in securing such an environment and establishes a series of requirements that future security architectures can be based on.